This invention relates generally to a technique and system for providing payments to health care providers.
Due to the geometric escalation of medical care costs, there is increased pressure on public policy makers to establish cost containment programs. For this reason state and Federal governments are beginning to adopt various case specific or case-mix reimbursement systems. The Social Security Amendments of 1983, (Public Law 98-21), specifically require a diagnosis specific prospective payment system to be incorporated into Medicare reimbursement policies.
The Federal government has therefore adopted a new payment plan for reimbursing hospitals for Medicare patient costs. Hospitals will be reimbursed according to a fixed schedule for each patient without regard to actual costs to the hospital in rendering medical services to the patient. The law provides for a 3-year transition period during which a decreasing portion of the total prospective payment will be based on hospitals' historical costs in a set base year and a gradually increasing portion will be based on a regional and/or national Federal rate per patient discharge. Beginning with the fourth year and continuing thereafter (i.e. cost reporting periods beginning on or after Oct. 1, 1986), Medicare payment for hospital inpatient services will be determined completely under a national DRG (Diagnosis Related Group) payment methodology. It is expected that this same reimbursement policy will in time be extended to establish the level of reimbursement to other health care providers and/or from other government entities and insurers.
The DRGs represent a clinical statistical classification effort to group together those diagnoses and procedures which are clinically related and have similar resource consumption. The DRGs are defined by a particular set of patient attributes which include a principal illness diagnosis, specific secondary diagnoses, procedures performed, age, sex and discharge status (i.e., how the patient left the hospital, whether the patient was transferred, died, etc.). A fixed reimbursement factor (relative weight) is assigned to each DRG by the government. This determines the amount the hospital will be reimbursed for treatment of a patient that falls within the DRG, regardless of the hospital's cost or what the charges would have been for a non-Medicare patient. The treatment of a patient during a single hospital stay is classified in only one DRG.
There are currently 467 DRGs which cover all patients treated under inpatient conditions. These are set forth in the regulations of the Health Care Financing Administration (See the Federal Register, Vol. 48, No. 171, Sept. 1, 1983, pages 39752-39886, for an Interim Final Rule that includes a listing of the DRGs and the reimbursement procedures involving their use. See also the Federal Register, Vol. 49, No. 1, Jan. 3, 1984, pages 234-334, for the Final Rule). Table I attached hereto gives the published information from these Federal regulations for a few DRGs as examples.
In addition to the 467 DRGs, there are three additional patient groups referred to as groups 468 through 470. DRG 468 includes patients for whom all surgical procedures were unrelated to their principal diagnosis. Group 469 includes cases where the principal diagnosis, while valid medically, is not accepted for DRG purposes as a principal diagnosis. Group 470 includes cases which could not be assigned to the other valid DRGs because of coding errors in that particular patient's medical records. DRG's 469 and 470 are not valid for payment. The more complex diagnoses that typically consume more resources should result in a more complex set of diagnoses and procedures and thus result in a higher paying DRG. (See the different relative weights in the example DRG's of Table I.)
Under the current version of this reimbursement system, the hospital does not directly determine the appropriate DRG category for services rendered a Medicare patient. Rather, the hospital submits an appropriate Federal form which includes codes from the ICD-9-CM coding system to identify the diagnoses made and procedures performed, and gives patient information that is relevant to determining the appropriate DRG category, such as age and sex. From this information, an intermediary reimbursing agent, or the Health Care Finance Administration itself, determines the proper DRG.
The commonly used notation "ICD-9-CM" means the International Classification of Diseases--9th Revision, Clinical Modification, and refers to a coding system based on and compatible with the original international version of the ICD-9 coding system provided by the World Health Organization. The ICD-9-CM coding system is used in North America, and it is a classification of diseases, injuries, impairments, symptoms, medical procedures and causes of death. These codes are listed in detail in a publication of the Commission on Professional and Hospital Activities, Ann Arbor, Mich., entitled "ICD-9-CM", Jan. 1, 1979. A exemplary list of a few ICD-9 codes is given in Table III attached hereto.
The ICD-9-CM coding system was designed for the classification of morbidity and mortality information for statistical purposes and for the indexing of hospital records by disease and operations for data storage and retrieval. The ICD-9 codes are initially divided into Disease and Procedure sections. These sections are further divided into subsections which encompass anywhere from 1-999 three digit disease or 1-99 two digit procedure code categories. Within the three digit code categories there can be an additional 1 or 2 decimal digits to divide the codes into subcategories which further define the disease manifestations and/or diagnostic procedures. There are approximately 15,000 ICD-9, codes. Only a fraction of these are relevant for determining Medicare payments. The new Medicare payment system first involves the coding of diagnostic and procedural information into ICD-9 code numbers by hospital medical records clerks before a patient can be assigned a DRG.
Each DRG is determined in part by an ICD-9 code for the principal diagnosis, and ICD-9 codes for each procedure that may have been performed. There are also ICD-9 codes for complications ocurring during treatment or the existance of co-morbidities (i.e., secondary diagnoses of conditions existing at the time of admission). These, as well as the patient's age, sex, and discharge status, determine a particular DRG for the patient. It is possible that a large number of sets of ICD-9 numbers or codes can lead to the same DRG. Some DRGs aIso require an ICD-9 code for a secondary diagnosis.
As can be seen from the DRG definition excerpts in Table I hereto, a patient's age is frequently a part of the definition. Pediatric patients (age 17 or less) and elderly patients (age 70 years or more) often fall into separate DRG categories that otherwise have the same textual definition. Where this occurs, the hospital is paid more for treatment of the older patient by assigning a higher paying DRG.
Also, the presence of a complication or comorbidity (collectively denoted in the DRG definitions as "C.C.") with a patient is required for many DRGs. The patient with a complication or comorbidity is considered to be a sicker person for certain illneses than one without a C.C. and the hospital is reimbursed more for those illneses by classifying such a patient in a higher paying DRG. However, not all medically recognized complications or comorbidities are recognized by the DRG reimbusement system to have any effect on the payment to be made. This and the entire DRG reimbursement system is decribed in the Federal Register referenced above.
Since the DRG method reimburses only specific amounts regardless of the actual costs, and since a large, significant proportion (some hospitals are 40% and higher) of the patients in most hospitals are Medicare patients, it is extremely important that the ICD-9 codes submitted for reimbursement be complete and accurate enough to assure that the highest correct paying DRG is assigned for each patient. The actual reimbursement that a hospital receives for each patient involves the multiplication of the relative weight of the DRG (see Table I) with other factors set by the government. These other factors are determined by statistical variables (e.g. the cost data of that particular hospital for the 12-month period ending on or after September, 1982 and before September, 1983, the type of patients a hospital treats in relation to the hospital's resources expended for those patients, and the wage and cost of living index). It is also important that the hospital is cost effective in handling this data as well as in caring for its Medicare patients. A hospital which is not cost effective will suffer severe financial difficulties. A cost effective hospital, however, may actually profit from this plan.
One technique for increasing the likelihood of accuracy and cost effectiveness in working with the new Medicare DRGs is to incorporate it into a computer system. A variety of computerized purely medical data handling systems exist, extending from a computer assisted system for taking patient medical histories as disclosed in U.S. Pat. No. 4,130,881 to a patient report generating system for reporting medical test data for an entire patient population. This system as disclosed in U.S. Pat. No. 4,315,309 organizes cumulative medical test data into data packages which include only the results of tests making up a particular organ system disease related subset of tests.
Two computerized systems also exist which relate directly to the Medicare DRG plan. The first of these is the DRG Grouper System which converts a single ICD-9 code or a set of ICD-9 codes and the other DRG related factors (age, co-morbidity, etc.) for a patient into the corresponding DRG category. This is public information that is available at cost. One company manufacturing an enhanced DRG Grouper is the DRG Support Group, Ltd., a subsidiary of Health Systems International, Inc. The second DRG related computerized system is provided by Code 3 Corporation. The Code 3 products are computer programs which use a medical encyclopedia as part of its database and calculates the DRG at the time the coding or abstracting is being done. Key words taken from a doctor's diagnoses are first entered into the computer. The computer then responds by offering other diagnostic conditions which have bearing on a DRG classification. Depending on the selection of other diagnostic conditions, the computer assigns an appropriate DRG. The Code 3 products can also store the DRG in the patient's abstract by utilizing a computerized abstractor.
These systems, however, still depend upon the ability of hospital medical records personnel who are not trained in clinical medicine but who are routinely responsible for preparing ICD-9 codes for reimbursement reports after the patient has been discharged from the hospital. The clerk necessarily has to search the usually thick patient chart in order to find conditions and procedures in order to identify the correct ICD-9, codes. This usually requires having to interpret various handwriting styles and different forms of notation that exist among physicians. Even more subjective is the necessity of medical records personnel to try to interpret clinical patient data to arrive at diagnostic data that can be coded for purposes of reimbursement. The physician may even fail to note information that is important for the purpose of reimbursement to the hospital because the physician does not consider it to have sufficient medical importance that would affect care of patients. Yet the obtaining of this information from the patient chart can be very important to the hospital since overlooked specific diagnostic and/or procedure information which was performed can cause assignment of a lesser value DRG. The result can lose the hospital money to which it is entitled. It has even been shown by studies conducted by the Institute of Medicine in 1974 and 1977 that such a method of coding diagnoses and procedures has a high rate of error because of these and other factors.
Therefore, it is a primary object of this invention to provide a computer system to assist any of the medical personnel involved in either the care of patients or quality assurance of such medical care, to determine reimbursement codes and categories that minimizes such errors, and thus to improve the accuracy and reliability of the information reported.
It is a further object of this invention to provide a computer system that minimizes the number of missed diagnoses or procedures that can increase the amount of reimbursement to the health care provider.
It is yet another object of this invention to provide a computer system that results in more accurate information from which cost and profit figures can be obtained for management purposes.